US2586691A - Excess flow check valve - Google Patents

Description

Feb. 19s 1952- E MILLS ETAL 2,586,691

Excss FLOW CHECK VALVE' Filed June 26, 1947 2 SHEETS-SHEET 1 Feb. 19, 1952 E. l.. MILLS Erm.

EXCESS FLow CHECK VALVE Filed June 261 19217 2 SHEETS-SHEET 2 Patented Feb. 19, 1952 UNITED STATES PATENT OFFICE EXCESS FLOW CHECK VALVE Ellsworth L. Mins, Highland Park, and Raymond R. Zimmer, Chicago, Ill., assignors to The Bastian-Blessing Company, Chicago, Ill., a corporation of Illinois Application `lune 26, 1947, Serial No. 757,118

This invention relates generally to check valves and more particularly to an improved excess ilow check valve which, in addition to closing automatically should the rate of iluid flow through it become excessive, may be opened or closed manually.

The valve of this invention, which is intended primarily for use with liqueed petroleum gas, but may be readily adapted for other fluids, is

further characterized by its being of greater sena Excess ow check valves are designed so that they will close and shut o the ow of fluid when the pressure on the upstream side of the valve exceeds that on the downstream side by a predetermined value or when the rate of ilow through the valve exceeds a predetermined rate.

Normally, excess flow check valves are not positive shutoff valves but are purposely designed so as to leak slightly with the result that when they have been closed, pressure will gradually build up on the downstream side as fluid leaks by and allow the valve to open.

The valve of this invention can be used in conjunction with pumps for transferring liqueecl petroleum gas from one container to another such as those employed to convey gas from a tank truck to a storage tank. When a conventional excess flow check valve is connected in series with such a pump in a conduit connecting two gas containers in order to transfer fluid from the one container to the other, diilculty is frequently encountered when the pump is first started, for, if the pump is of a large capacity, immediately it is started it delivers liquid to the upstream side of the excess ilo-w check valve at a substantially high pressure compared with the zero pressure present downstream of the valve. Since these valves actually operate on pressure differentialrrather than rate of ilow, the abnormal differential experienced kwhen the pump is rst started causes the valve to slug closed. When this occurs, a delay period of fteen to thirty 12 Claims. (C1. 137-153) minutes must be taken until sufcient fluid has leaked past the valve through the small bleedhole provided to build up the downstream pres-v sure so that the valve can reopen. The same inadvertent slugging described above will occur when a control valve in a line connecting a full container through a conventional `excess flow check valve to an empty container is opened too rapidly.

One object of this invention therefore is to provide a valve which may be manually forced open by the operator should it slug closed under these conditions.

Another object is to provide a valve which may be manually closed and thus eliminate the neces-"Q sity for providing a separate shutoff valve in the`A line, or allow the shutoi valve to be serviced Where one is provided.

A further object is to provide an excess flow check valve which can be manually closed as a shutoi valve to form a substantially tight leakless seal, but which leaks slightly when closed automatically, rather than manually,l in order that the valve will open automatically should it close and the operator fail to open it manually.'

A further object is to provide a valve having a triangular shaped port closed by movement of the valve member across the port, the member' moving from the base of the triangle to its apex in order to close oif the port more rapidly during the initial stages of closing to eliminate the posto the section of Fig. l showing the valve in the' automatically closed position.

Fig. 3 is a section showing the valve in the normally open position.

Fig. f1. is a section showing the valve in the manually forced open position.

Fig. 5 isa View showing the operating lever and its associated linkage.-

Fig. 6 is a partial section showing the method of attachment of the operating crank to the rotambie shaf15A L l i ed petroleum gas or other fluid under pressure while the pipe I l extends to the tank (not shown) into which the fluid is to be transferredso Athat j the direction of fluid flow isirom..the pipe .IZ

to the pipe i i as indicated bythe arrowin Fig. im,

Although the valve i8 is shown Vinstalled in..

a conduit, it may be installed directly on the tank itself, a threaded flange being provided in a wall of the tank. need not be installed in the vertical positionbut may be placed horizontally or inverted from the position shown. However, for greatesty accuracy,

positionat which it is .to be installed.

The major portion of the valve I- isiormed of.:

erably formed of castY brassandis threaded on each` end as indioatedat i4 and i5 for attachmenttolthe pipesl and I2., A passage I6, whose lower end is of smaller diameter, extends through thebody.I3fromone end to the other. A pr.0

lecton I'I-,onthe lower end oithe body is providedwiththreads I8 for supporting the cylindrical valve guide I9.

The valve guide I9, preferably machined from a piece of. tubing, is provided lwith an internal shoulder ZI Yand itsinternally threaded at each end.. Four ports or openingsv 22 are cut throughv the sidewallsof the guide I9 at th'eupper end. As shown in Fig. '7, the ports 22 are triangular in shape.v

The cupped` shape valve member 24-is receivedv inside of the guide I9 and retained therein by-.adise-like stop 25' screwed into the threads-*23. l A

coil spring 2 surrounds the valve member 24:?and

urges it downwardly bearing against the shoulder,

2|.r and a second shoulder 28l on'zthememiverff. Thus the member 24is normally in theposition shown in Fig. l3.: Thestop is providedwith-a hole ZEathereth-rough to admit fluid'to the space- To adjust .the rate` oi.-flow within the-guide IS. atwhichthevalve II! closes, the spring 2'I-may be replaced-by a stro-nger or weaker springr;

Thebottom-'faceof the projection i'Lonithek body I3 is machined oil flat, as is .thetop of, the;

memebr -2-4,A to ,form a valve seat. 3G against. which the valve `member 24 closes to formaseall The apparatus. as.. so vfar. described includes. those .elements-necessary .to an..automaticelly.

operating excess flow check valve. The following,

description relates to the elements which comprise the manual operation drive for manually opening and closing of the valve.

A hole 33 is drilled through the upper end of the member 24 and receives the end of the operating vshaft 34. The lower portion 35 of this shaft is `of sufficiently less diameter than the hole 33 to allow a small volume of fluid to flow through the space surrounding the shaft 34 when the valve is inthe ,slugged or closed position. This ,space replaces the bleeder hole provided in conventional excess flow check valves, allowing `fluid to leak past the valve member-24 Vat aslow rate in order that ,the valve may unseat itself in ease it has accidentally/'been allowed to slug closed or where the valve controlling discharge is operated to-provide excessive ow. The lower end of the shaft'34 is Furthermore, the valve Il] .2U a-givenvalvemust be setor adjustedfor the threaded and receives a nut 36 whose upper face is machined flat so as to seal the opening 33 when the member 24 rests against the nut 36.

The upper end 0f the shaft 34 is provided with a square head 3l which is drilled as indicated at 38 to receive a pin 40. A rib 4I, integral with the body 3I3,=extends across the passage I-B, and has a vertical hole 42 drilled through it for supporting the shaft 34.

A boss 43 (Fig. 2) is provided on oneside of the ,'bodvlf` I3 vfor supporting a threaded bushing 44. This -bushing is screwed into a threaded hole 45; asealbeingeffected by a gasket 46. On the opposite sidev of, the body i4 and on the same centerlineasthe threaded hole 45, a hole 4l is drilled for supporting the end at a crank shaft 4S. The other end of` this shaft is supported in a hole 49 provided in another shaft 5U which extends through the bushing 54., The two shafts 48 and 50 are joined together by a pin 5 I.

The innerend of the shaft' is of larger-diameter thanl the remainder and has ya ring-likeprojection 52 machined thereon.- Thisprojection bearsl 'against an Aannular ring 53 of elastic materialcarried by the bushing 44 and seals the shaft 50 to the bushing,

The outer endV of the Ashaft 5Il, as shown in 6, is machined square to receive a crank arm 54 having a square hole 55; The hole 55` is slightly larger than the end of the shaftv 5G soH that the arm- 54 is slidable with respect tothe shaft 50. A nut 56 carried bythe end of the shaft isupports aspring 51 which bears against the'arm 54; to tend to pull the shaft 5i! `outwardly and eliect a-tight seal between the gasket 53V and the annularprojection or seat 52, any pressure present inthe passage I6 augmenting the springnpressure to increase the eioiency of the seal.

The shaft48; whose center portion issquarein cross section, carries a crank S0' rigidly-attached thereto as shown-in Fig. 1. A link 6| is attached to the end of the crank 60 by a pin- A iulcrum pin 35 passes through the lever- 63 and is secured to the rigidly mounted plate 64. A second plate 68 is bolted to the plate 64 and has a pair of slots El and 68 cut into it.v ThetopY edge of the plate 65, `as viewed in Fig. 5, is

cut out along an'arcuate line having its center4 at the `iulcrum of the lever G3. The slots 61 and 6B are Ycut into this curved edge. A rod 10, attached to the )handle 53, is urged downwardly bye, spring II. A handle I2 pivoted on the end ofthe lever 33 is linked to the rod 'Ill by a lever 13.50 that when the handle I2 is squeezed inwardly toward the lever 63, therod I0 will be drawn upwardly into the lever 63, and when the handle 'I2 is released, the end of the rod 'I0 will tend to project beyond the end of the lever 63.

Thusv the lever; t3l may be locked in'either ofA movement of the lever 63 beyond the locked position when the rod is inserted in the slot 68, but the stop 16 allows the lever B3 to be moved slightly beyond the position of the slotYl Thus the lever 63 may be locked in either of two positions or moved to a third position as l limited by the stop 16. The handle 63 is shown in the manually closed position.

The operation of this device is as follows: Assume that the handle S3 hais been moved to the position indicated at 80 in Fig. 5. The valve it. This forces the member 34 downwardly, the

I0 is now in the normal open position, the various internal members being positioned as shown in Fig. 3. y I0 at a rate below the critical value, the valve member 24 remains in the position shown, beingV held in this position by the spring 21. The fluid flows through the pipe I2 and into the annular If uid is owing through the valve:

space formed between the valve guide I9 and the pipe wall. From this space the fluid passes inwardly through the triangular holes 22 into the passage IB within the body I3 from which it flows into the pipe II.

As the rate of flow through the v alve I0 1n creases, the pressure differential between the pressure upstream of the valve and that downstream caused by friction of the fluid in flowing through the valve also increases. As soon In the event that thel valve I0 has slugged closed and it is desired to quickly open the valve' I0, the operator need only move the handle 63 tothe position indicated at 8| in Fig. 5. When this is done the internal parts assume the positions shown in Fig. 4. The shaft 48 is rotated slightly in the clockwisedirection from the position shown in Fig. 3, carrying the crank Bil with shoulder a bearing against the top of the valve member 24 and forcing it away from its seat 30.

As soon as this is done, uid flows freelykp-ast the valve member 24 and quickly builds up sufficient pressure downstream to allow the member 24 to be returned to its fully opened position by thespring 21. When the member 24 has returned to the open position the handle 63 may be returnedto the position indicated at 80 and the valve I will remain open.

When it is desired to employ the valve IU as a shutoff valve, the handle 6 3 is thrown to the position shown in solid lines in Fig. 5. This causes the shaft48 and crank 60 to rotate to theV position shown in Fig. 1, moving the operating shaft 34 upwardly. The nut 36 on the end of-` f this shaft draws the member 24 upwardly until as this pressure differential is sufficiently great, y

the upstream pressure acting on the bottom side of the valve member 24 through the hole` 25a in the disc 25 is suicient to overcome the force of the spring 21 and move the valve member 24 upwardly. As soon as this member moves upwardly its top edge closes oi a portion of eachv of the triangular holes 22, restricting the ow through the valve .|0. This increased restriction causes the pressure differential to become greater in this manner, in order to open it against presso that the valve member moves farther up-fy wardly closing the ports 22 further. 'I'hus the instant the pressure differential exceeds the critical value, the valve member moves rapidly to the fully closed position as shown in Figj2 and remains in this position.

The triangular ports 22 havevbeen found to have particular advantages over the conventional round or other shape ports. By employing triangular ports, the rate of closing of the ports is greatest at the start of the valve members movement sov that the pressure differential across the valve I 0 is immediately increased substantially;

the rate of increase being greater than the in' f crease in the force required to compress the spring 21. Thus once the valve member 24 starts to move upwardly, it closes completely and will not hunt or chatter as it seeks to come to an equilibrium position balancing pressure differential against spring compression as may be the case when nontriangular ports are employed.

eventually builds up sufcient pressure down'- stream of the valve i0 so that the pressure differential is no longer greater than the force of the spring 21 and the valve member 24 will be forced back to its original position. However,

as' has been 'pointed out, this procedure requires considerable time, particularly when the pipe II is of great length.

sure the handle 63 must be moved to the position indicated at 8 I. position the valve will open slowly, for considerable time is required for sufficient pressure to bleed past the valve to allow it to open automatically.

The plate 66 (Fig. 5) is purposely provided with only two locking slots 61 and 68. No slot is provided to permit the handle 63 to be locked in the manually opened position indicated at 8l. for it would be unsafe practice to enable an operator to lock the valve III in the open position.

Various changes or modifications such as the provision of an elastic valve seat ordisc for the member 20 to form a better seal, or the substitution of a simple handle provided with locking detents directly on the valve body I 3 eliminating the linkage shown in Fig. 5 and others which will be apparent to those familiar with the art may be made inthe embodiment illustrated without departing from the spirit of this invention whose scope is dened by the appended claims.

YWhat is claimed is: 1

l. In an excess flow check valve the combination including a hollow cylinder, a plurality of triangular shaped valve ports for the passage of fluid through the walls of said cylinder, a valve seat adjacent said valve ports disposed on a plane transverse to the axis of said cylinder, a valve member movably mounted in said cylinder for closing said ports and sealing against said seat when in one position, said member being so disposed as to be subjected to the force of the owing fluid, a spring for urging said member to a second position, said spring being so formed as to' yield when the force of the flowing fluid exceeds a predetermined value,and means for conducting If the handle 63 is moved to the 'SB-.id:Cylnder-gsaidports having.thebase-portionsofgthe trianglesvldisposedfsothat motion of-:said member from-:said;secondeposition inthe direction of said-first mentionedpositiorrcloses off the base portionrof-saidports rst finallyclosingoi the` apexes of the triangular ports.

2.. Inl an f excess: flow .check valve the combina-` tion including a hollowcylinder, a triangular shaped valve port for fthepassage of iiuid through the wall of said.cylnder,arvalveiseat adjacent saidvalve port disposed cna plane transverse to the. axis of :said cylinder, a valve member movablymounted in said cylinder for closing saidport and sealing against ,said seat when in. one position, said valve member being vdisposed in ther-path `of themovinguid soas to besubjeoted to the force thereof, a spring., Vfor urging ,said member to -a second position, said spring.,beingof such sizeas toyield permittingthe valvemember. to close when the flowing huid exerts a predetermined force thereon, and means ,for conducting a vstream of ,fluid to said port, said port having thewidest portiondisposedremote from saidwseat so .that

motion of said member from said second position toward said seatcloses .o' said widest portion .of said port iirst. A

3.11m an excessow check valve thecombination ,including a hollow cylinder, a plurality of triangularshaped valve ports forthepassage of close in the direction `of iuidflow,` a` spring forV urging said member to a sectmdposition,` said spring being of such size as .to yield underthe pressurel of 'iiuid owingabove a predetermined rate, l and' means ,for conducting, an annular stream of fluid to said ports: outside of said cylinder, said ports having0 the base portions of the triangles disposed so that motion of said member from said second position toward said valve seat closes oi the base portion of said ports first finally closing off the apexes of the triangular ports.

4; In an excess flow check valve the combination including a movable valve member positioned according tothe diierential in pressure across said valve resilient means for 4holding said valve open'adapted to `yield and allow said valve toA asV it moves from an-open-position to a closed y position, said valve ports being substantiallyl triangular inshape so that the rate of 'closing of said ports is at ama-ximumas said valve member starts to close, decreasing as said ports are closed.

5. In an excess flow check valve the combination including a movable valve member positioned according to the differential in pressure across saidvalve, a cylindrical guide member surrounding said valve member, a plurality of vvalve ports opening through said guide member'and adapted to be closed off 4by said valve member as it moves from an open position to a closed positionfsaid valve ports being substantially triangular inv shapeso that the rate of closing of said portsvis aspring for urgingsaid ,valve member towards said open position, saidspringbeing ofsuch size.

l as to. yield .under fluid pressure ;.permitting the valve to nos@ when the rare .ofy fluid .ndwrexa ceedsazcertain value.

6. Inf'an excess flowv check valve the .combina-- tion including av movable valve member, a cylin-.Y drical guidemember surrounding said-valvemem--- ber, a valve port opening through said guide member. and adapted to be closed oif by saidv valve member as it moves -froman open positionto a: closedposition, said valve port having one .end wider than the other end so that the rate of4 closing-of said port is at a maximum as said valve member starts to close, decreasing as said vports areclosed, and a spring for urging said .valve member -towards said open position, said springbeing of such size as to yield under fluid pres--- sure permitting the valve to close when the rate. of uid flow exceeds a certain value.

'7. An excess ow check valve comprisingan elongated body having a passage therethrough,

, a valve seat at one end of said body, a cylindrical,

valve guide attached to said body and surrounding-said seat, a movable valve member disposed within said valve guide and closing in .thedirection of fluid flow, a spring for urging said. valve member away from said valve seat, said .spring being so formed as to yield when the force exerted by fluid flowing past said member exceeds a pre.- determined value, and a plurality of valve ports opening through the wallsof said valve guideand adapted to be closed by said valve member, means` for positioning said valve member includinga reciprocable shaft mounted in said body, means on said shaft for engaging said valve member so constructed and arranged that in one position said shaft positively holds said member away from said seat and in another position said shaft positively holds said member adjacent said seat.

8. An excess flow check valve the combination including a body having a passage therethrough, a valve seat at one end of said body, a movable valve member disposed to cooperate withV said seat, a spring `forurging said valve member `away from said valve seat, means for positioning said valve member including a reciprocable shaft mounted within said body, means on said shaft for engaging said valve member so .constructed and arranged that in one position said shaft positively holds said member away from said seat and in another position said shaft positively holds said member adjacent said seat, said valve member being movable independently of said shaft and said spring being of such strength as to pere mit said valve member to move into contact Ywith said seat when the pressure thereon due to the flowing fluid exceeds a predetermined value. I

9. An excess now check valve comprising an elongated body having a passage therethrough, a valve seat at one. end of said body, a cylindrical valve guide attached to said body and surroundingsaid seat, a movable valve member disposed within said valve guide, a spring for urging said valve member away from said valve seat, and-a plurality of valve ports opening through the walls of said valve guide and adapted to be closed by said valve member, means for manually positioning said valve member including a reciprocable shaft mounted insaid body, meansV on said shaft for engaging said valve member-with substantial lost motion so constructed and, arfranged that in one position said shaft positively holdssaid member away from said seat, and in anotherposition said shaft positively holds said member adjacent said seat, and in athird posi:-V tion said valve member may moveindependently of said shaft to open or close:according'` tothe 9 pressure diierential developed by iiuid flowing through said ports, saidi spring being of such strength as to yield and permit said valve member to move against said seat when the pressure differential between the upstream andthe down stream side of the valve exceeds a predetermined value.

10. An excess iiovv check valve comprising an elongated body having a passage therethrough, a valve seat at one end of said body, a cylindrical valve guide attached to said body and surrounding said seat, a movable valve member disposed within said valve guide, a spring for urging said valve member away from said valve seat, and a plurality of triangular shaped valve ports opening through the walls of said valve guide and adapted to be closed by said valve member, means for manually positioning said valve member including a reciprocable shaft mounted in said body, means on said shaft for en gaging said valve member with substantial lost motion so constructed and arranged that in one position said valve member may move independently of said shaft to open or close according to the pressure differential developed by iiuid owing through said ports, said ports being disposed so that said valve member in moving toward said seat closes off the base portions of said triangular ports, said spring being of such strength as to yield and permit said valve member to move against said seat when the pressure differential between the upstream and the downstream side of the valve exceeds a predetermined value, and first and finally the apex portions.

11. In an excess ow check valve the combination including an element having a plurality of ports therein, a second element cooperating with the first element to close said ports, one of said elements being movably mounted with respect to the other element and being disposed in the path of fluid flowing to said ports, the movable element being subjected to the pressure of fluid upstream of said ports, and resilient means for urging the movable element against the force of flowing fluid to open said ports, said ports being so shaped that` the rate of closing thereof increases more rapidly than the rate of movement of the movable element.

12. In an excess flow check valve the combination including an element having a port therein, a second element cooperating with the rst element to close said port, one of said elements being movably mounted with respect to the other element, the movable element being subjected to the pressure of uid upstream of said port, and resilient means for urging the movable element against the force of flowing fluid to open said port, said port being so shaped that the rate of closing thereof increases more rapidly than the rate of movement of the movable element as the movable element moves to close the port.

' ELLSWORTH L. MILLS. RAYMOND R. ZIMMER.

REFERENCES CITED The following references are of record in the file of this patent: v UNITEDy STATES PATENTS Number Name A Date 657,707 Reese Sept. 11, 1900 727,484 Strnad May 6, 1903 1,039,520 Graetz Sept. 24, 1912 1,123,123 Grabler Dec. 29, 1914 1,142,219 Ziegler June 8, 1915 1,492,980 Hodges May 6, 1924 1,545,821 Eubanks July 14, 1925 1,919,955 Leech July 25, 1933 2,307,949 Phillips Jan. 12, 1943 FOREIGN PATENTS Number Country Date 490,008 France of 1918 778,928 France of 1935

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